com.dasasian.chok.protocol.upgrade.UpgradeRegistry Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of chok-core Show documentation
There is a newer version: 1.7
/**
 * Copyright (C) 2014 Dasasian ([email protected])
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.dasasian.chok.protocol.upgrade;

import com.dasasian.chok.protocol.InteractionProtocol;
import com.dasasian.chok.protocol.metadata.Version;
import org.apache.log4j.Logger;

import java.util.HashMap;
import java.util.Map;

public class UpgradeRegistry {

    private static final Logger LOG = Logger.getLogger(UpgradeRegistry.class);
    private static Map _upgradeActionsByVersion = new HashMap<>();

    static {
        registerUpgradeAction("0.5", "0.6", new UpgradeAction05_06());
    }

    protected static void registerUpgradeAction(String fromVersion, String toVersion, UpgradeAction upgradeAction) {
        _upgradeActionsByVersion.put(new VersionPair(fromVersion, toVersion), upgradeAction);
    }

    public static UpgradeAction findUpgradeAction(InteractionProtocol protocol, Version distributionVersion) {
        Version clusterVersion = protocol.getVersion();
        if (clusterVersion == null) {
            // version exist up from 0.6 only
            boolean isPre0_6Cluster = protocol.getZkClient().exists(protocol.getZkConfiguration().getRootPath() + "/indexes");
            if (isPre0_6Cluster) {
                LOG.info("version of cluster not found - assuming 0.5");
                clusterVersion = new Version("0.5", "Unknown", "Unknown", "Unknown");
            } else {
                clusterVersion = distributionVersion;
            }
        }
        LOG.info("version of distribution " + distributionVersion.getNumber());
        LOG.info("version of cluster " + clusterVersion.getNumber());
        if (clusterVersion.equals(distributionVersion)) {
            return null;
        }

        VersionPair currentVersionPair = new VersionPair(clusterVersion.getNumber(), distributionVersion.getNumber());
        LOG.warn("cluster version differs from distribution version " + currentVersionPair);
        for (VersionPair versionPair : _upgradeActionsByVersion.keySet()) {
            LOG.info("checking upgrade action " + versionPair);
            if (currentVersionPair.getFromVersion().startsWith(versionPair.getFromVersion()) && currentVersionPair.getToVersion().startsWith(versionPair.getToVersion())) {
                LOG.info("found matching upgrade action");
                return _upgradeActionsByVersion.get(versionPair);
            }
        }

        LOG.warn("found no upgrade action for " + currentVersionPair + " out of " + _upgradeActionsByVersion.keySet());
        return null;
    }

    protected static class VersionPair {
        private String _fromVersion;
        private String _toVersion;

        protected VersionPair(String fromVersion, String toVersion) {
            _fromVersion = fromVersion;
            _toVersion = toVersion;
        }

        public String getFromVersion() {
            return _fromVersion;
        }

        public String getToVersion() {
            return _toVersion;
        }

        @Override
        public String toString() {
            return getFromVersion() + " -> " + getToVersion();
        }
    }

}